The principal policy focus for food has been to increase agricultural productivity and to liberalize markets allowing globalized trade. This focus has led to huge growth in the supply of agricultural produce, more calories becoming available, and price declining. The availability of cheaper calories increasingly underpins diets creating malnourishment through obesity, and global competition incentivizes producers who can produce the most, cheaply, typically with environmental damage. We propose re-focusing, away from yields per unit input, to the food system's overall productivity and efficiency – the number of people that can be fed healthily and sustainably per unit input.